A. Field of the Invention
The present invention relates to a method and system for automatic image-property identification for a scanner, especially for the information reading process of an optical scanner which requires a prescan.
B. Description of the Prior Art
The information reading process of a conventional optical scanner usually requires two steps: Prescan and complete scan. The prescan is mainly for finding the border of the sheet and its coordinates on the document tray. It reads the information of the sheet at a higher speed because its resolution requirement is only about 30 dpi. Then, the rough image of the original sheet will show on the screen for the user to circumscribe the desired region by dragging and clicking the mouse. After the region is determined, the photoelectric converting device will move to the target position for a complete scan. At this time, the speed of scanning is slower because it requires a higher resolution of about 600 dpi.
The disadvantages for this procedure are that it requires two steps and it could not automatically identify the image properties for the sheets of commonly-used sizes, such as 4A sheet, a 4.times.4 or 3.times.6 photo, slides or name cards. This disadvantage will turn out to be a burden for a user when he/she has to scan a large amount of sheets and especially on a routine bases.